^2,7 



Polyg'oiiiiiii eiiiersuni, (Mich.) Britton. Swamp Persi- 

 caria. 



In swamps and edges of ponds throughout the state. 



Polygoiiuiii lapatliilbliuiii, L. Dock-leaved Persicaria. 

 In waste places throughout the state; rare west of the 

 Missouri, except in the Black Hills. 



Polygonum lapathifolium iiicaiiuin, (Schmidt.) Kock. 

 Same range as the type. 



Polygoimni Peiiii.sylvaniouiii, L. Pennsylvania Persi- 

 caria. 



In moist soil from the Missouri valley eastward. 



Polygonum Persicaria, L. L,adies' Thumb. 



Common in waste places from the Missouri valley 

 eastward, and in the Black Hills. 



Pol,>gonum liydropiper, L. Smart-weed. 



In moist places in the Minnesota and Sioux valleys. 



Polygonum punctatum, Ell. Water Smart-weed. 

 Polygomini acre, H. B. K. 



In cold swamps in the Minnesota valley. 



Polygonum aviculare, L. Knot-grass. 

 In waste ground throughout the state. 



Polyg'onum littorale, Liuk. Shore Knot-weed. 

 In waste places in the Black Hills. 



Polygonum erectum, L. Erect Knot-weed. 

 In dry soils throughout the state. 



Polygonum ramosi.ssimum, Michx. Bushy Knot-weed. 

 A cpmmon weed in dry soils, throughout the state. 



Polygonum famporum, Meisu. Prairie Knot-weed. 

 On prairies from the Missouri river eastward. 



Polygonum tenue, Michx. Slender Knot-weed. 



In ground that has been broken from the Missouri 

 river eastward. 



